T H E B R I T I S H J O U R N A L O F A N I M A L B E H A V I O U R

The Herring Gull's World. By N. TINBERGEN. London: Collins. 1953. Pp. 255, 51 photo- graphs, 58 drawings and diagrams. 18s.

Dr. Tinbergen's recipe for the study of a new species is first observation, and then observation, experiment and comparison. In this masterly analysis of the life of the Herring Gull he allows us to see his technique in action: no one in- terested in animal behaviour can afford not to read it.

The greater part of the book is devoted to the reproductive behaviour of the Herring Gull and demonstrates clearly the importance of observation in the analysis of behaviour. Of course it is not sufficient for the observation to consist merely of the collection of fac ts - - reading this book one can see how Dr. Tinber- gen's success depends on constantly asking the right questions ("Even an hour 's careful obser- vations of the goings on in a gullery faces one with . . . more problems . . . than one could hope to solve in a lifetime."), and on continually analysing the facts which he collects to answer them.

These questions are not confined to the im- mediate causation of behaviour- - though this is the central t heme- -bu t are also concerned with its significance in the life of the bird and its elaboration during the course of evolution. These three approaches combine to give an all-round and extraordinarily vivid picture of the Herring Gull 's world. In particular, the analyses of threat and courtshi p behaviour, which have already set the pattern for similar analyses in other species, are of special import- ance: these alone would suffice to make this a book of reference for a long time to come.

Later in the book Dr. Tinbergen describes some experimental work designed to elucidate how Herring Gull 's "recognise" their eggs, and to analyse the stimuli which release the pecking of the chick. These experiments are a development of the observational analysis-- they were made in the field and, unlike so many experiments on animal behaviour, are related to the normal life of the bird.

Throughout, Dr. Tinbergen frequently com- pares his findings with those obtained f rom other species. This comparative approach both facil- itates the analysis of the behaviour in question, and enables the generality of the conclusions to be assessed.

As well as being of outstanding importance for students of bird behaviour, this book is a

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pleasure to read. It is written with great vivid- ness and charm: the gulls are real gulls, not biological abstractions, and the problems are meaningful ones.

The 51 photographs are technically excellent: further, they are not just a collection of the "parent bird at nest" type, but a carefully organ- ised record of the behaviour patterns discussed. As a collection they must be unique.

R.A.H.

An Analysis of' the ParentaI Behaviour of the Male Three-spirted Stickleback (Gasterosteus aeul~ eatus). J. J. A. VAN IERSEL. Behaviour. Supple- ment No. 3. Pp. 1-139. For many years a handful of species--

Dogfish, Cockroach, Frog, Rat, Sea Urchin, Drosophila and a few others--have, in their several fields, been the classic animals of Zoology. Now, as a result of the work started by Dr. Tinbergen and carried on by his pupils and colleagues at Leiden University, the Three- spined Stickleback has j oined them. Only a small section of this work has so far been published, and Dr. van lersel'S monograph is the first detailed study to appear.

Once the male stickleback has settled on a territory, three fairly distinct phases in the reproductive behaviour can be recognised-- nest-building, sexual, and parental. Each is marked by the frequent occurrence of certain characteristic activities. In this work the factors causing the change f rom the sexual to the parental phase are elucidated. The method used is, in principle, simple : the amount of "fanning" (the behaviour by which the male aerates the eggs in the nest) is used as an index of parental activity; and the number of zig-zag dances (a courtship activity) given in a standard time to a standard stimulus as a measure.of the sex drive. Various external factors are manipulated (in particular the number of times the male is allowed to fertilize, and the number and age of the clutches in his nest) and their effects assessed.

Dr. van Iersel applies this method with extra- ordinary effectiveness. The relentlessness with which he analyses the problem and then tracks down and elucidates one relevant factor after another should serve as an example for all future experimental work of this type. The argument, though necessarily complicated by the thoroughness of the analysis, is clearly set out: at every stage the evidence for each deduc- tion is presented and due notice taken of altern- ative interpretations.